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Aerodynamic-load calculation in aero-hydro-servo-elastic modeling tools has been recently validated against experiments for low-frequency platform motions but without considering the capability of active wind turbine controls. This work presents a control design framework that allows for including industry-standard wind turbine control functionalities in a model-scale rotor and its application to a 1:100 scaled version of the International Energy Agency (IEA) 15 MW turbine. Wind tunnel tests with a fixed foundation and steady wind show the scaled turbine reproduces the steady-state rotor speed–blade pitch–thrust–torque characteristics of the IEA 15 MW turbine, confirming the controller design method. Tests with a prescribed platform pitch motion are carried out to assess the turbine response and controller modeling in conditions representative of the normal operation of floating wind turbines. The blade element momentum model of OpenFAST is verified against the experiment, showing aerodynamic thrust and torque are predicted with higher accuracy in the below-rated than the above-rated region: in our simulation, the decrease in thrust oscillation amplitude due to blade pitch actuation is underpredicted. This, combined with uncertainty in modeling the blade pitch actuators, complicates the numerical–experimental simulation of the turbine aerodynamic response in above-rated operation.

The phenomenon of deforestation is occurring globally, in different types of forests, and for various reasons. In Africa, an estimated 90 per cent of the entire continent's population uses wood as a source energy for heating and cooking. However, the unsustainable harvesting of trees for heating energy not only contribute to forest and environmental degradation, but it is also a significant contributor to ill health, air pollution and climate change. Reducing the resulting adverse of ecological and health consequences will have to involve a mix of adopting renewable fuels and natural resource sustainable strategies. To date, implementing this mix has shown significant challenges, especially in developing countries. We performed this systematic literature review (SLR) to help us better understand how research is approaching this mix in Africa. We screened 792 articles resulting in a final selection of 34 studies concerned with environmental sciences. The review drew on qualitative, quantitative, and regional studies and applying a standardized method for screening, data extraction and synthesis. The findings reveal that current research focuses dominantly in four key areas: (1) renewable technology transfer, (2) climate change-adaptability, (3) climate policy, and (4) technology adoption. However, we identified a literature gap on the thin literature concerned with the impact of clean technologies to improving the environment and people's wellbeing. We propose planning a tool that would facilitate this process and suggest further research to incorporate monitoring its effectiveness., (© 2022. The Author(s).)